Prosthetic sock for reducing movement between residual limb and prosthesis and method for use

ABSTRACT

A prosthetic sock for reducing movement of a residual limb within a prosthetic socket of a prosthesis includes a stretchable prosthetic sock having an inner surface and an outer surface, and a movement-opposing material disposed partially on the inner surface and outer surface for reducing the residual limb movement so as to leave areas about a circumference of the prosthetic sock without the movement-opposing material. The prosthetic sock may be a cotton cloth material, and the movement-opposing material may be latex laminated on the inner and outer surface of the sock.

This application is a continuation of U.S. patent application Ser. No.08/371,359, now U.S. Pat. No. 5,728,167, filed on Jan. 11, 1995.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention generally relates to prosthetic deviceaccessories. More particularly, the present invention relates toprosthetic socks or sheaths.

2. Background Information

In the past, prosthetic socks have been used by amputees to providecushioning and a proper fitting for a residual limb within a prostheticsocket of a prosthesis. Typically, a snug-fitting and conforming suctionsocket sleeve is placed over the residual limb, and covered with one ormore prosthetic socks. The prosthetic socks are commonly made of astretchable material, such as cotton or wool, and are available indifferent thicknesses from a single ply to multiple plys. Although suchprosthetic socks do provide the cushioning and proper fit within theprosthesis, the smoothness of the sock may cause slippage of theresidual limb relative to the prosthesis. This movement is especiallyacute in above-the-knee amputations, however, varying degrees ofmovement may be found with any residual limb, including arms.

Solutions to this problem have included straps and harnesses to preventthe movement of the residual limb. However, such solutions complicatethe process of donning the prosthesis for the amputee, restrict motionand increase discomfort.

Thus, a need exists for a way to reduce movement of a residual limbrelative to a prosthesis without adding other mechanisms that complicatethe prosthesis donning process.

SUMMARY OF THE INVENTION

Briefly, the present invention satisfies the need for a way to reducemovement of a residual limb relative to a prosthesis without addingadditional mechanisms to the prosthesis donning process by providing aprosthetic sock with a movement-opposing material disposed on an innerand outer surface thereof.

In accordance with the above, it is an object of the present inventionto reduce the movement of a residual limb relative to a prosthesis forthe residual limb.

It is another object of the present invention to provide a prostheticsock for reducing the movement of a residual limb relative to aprosthesis therefor.

The present invention provides, in a first aspect, apparatus forreducing movement of a residual limb relative to a prosthetic socket ofa prosthesis. The apparatus comprises a prosthetic sock fabricated of afirst material, and having an inner surface and an outer surface. Theapparatus further comprises a movement-opposing material disposed onlypartially on the inner surface and disposed only partially on the outersurface. The movement-opposing material comprises a second materialdifferent from the first material. The movement-opposing materialdisposed on the inner surface opposes movement of the residual limbrelative to the prosthetic sock, and the movement-opposing materialdisposed on the outer surface opposes movement of the prosthetic sockrelative to the prosthetic socket. The movement-opposing material isdisposed on the inner surface and the outer surface so as to leave aplurality of areas about a circumference of the prosthetic sock withoutthe movement-opposing material.

The present invention also provides, in a second aspect, a system forreducing movement of a residual limb relative to a prosthetic socket ofa prosthesis. The system comprises a suction socket sleeve for placingover the residual limb, the suction socket sleeve conforming to theshape of the residual limb, and apparatus for covering the suctionsocket sleeve prior to placement within the prosthetic socket. Theapparatus comprises a prosthetic sock for placing over the suctionsocket sleeve, the prosthetic sock being fabricated of a first materialand having an inner surface and an outer surface, and amovement-opposing material only partially disposed over the inner andouter surfaces. The movement-opposing material comprises a secondmaterial different from the first material. The movement-opposingmaterial disposed on the inner surface opposes movement of the suctionsocket sleeve relative to the prosthetic sock, and the movement-opposingmaterial disposed on the outer surface opposes movement of theprosthetic sock relative to the prosthetic socket. The movement-opposingmaterial is disposed on the inner surface and the outer surface so as toleave a plurality of areas about a circumference of the prosthetic sockwithout the movement-opposing material.

The present invention further provides, in a third aspect, a method ofusing a prosthetic sock to reduce movement of a residual limb relativeto a prosthetic socket of a prosthesis. The prosthetic sock isfabricated of a first material and including a movement-opposingmaterial partially disposed over an inner surface and partially disposedover an outer surface thereof, the movement-opposing material comprisinga second material different from the first material. Themovement-opposing material is disposed on the inner surface and theouter surface so as to leave a plurality of areas about a circumferenceof the prosthetic sock without the movement-opposing material. Themethod comprises the steps of: placing a suction socket sleeve over theresidual limb, the suction socket sleeve conforming to the shape of theresidual limb; placing the prosthetic sock over the suction socketsleeve; and inserting the residual limb with the suction socket sleeveand the prosthetic sock thereon into the prosthetic socket. Themovement-opposing material disposed on the inner surface opposesmovement of the suction socket sleeve relative to the prosthetic sock,and the movement-opposing material disposed on the outer surface opposesmovement of the prosthetic sock relative to the prosthetic socket.

These, and other objects, features and advantages of this invention willbecome apparent from the following detailed description of the variousaspects of the invention taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a residual leg below the knee covered with a suctionsocket sleeve and prosthetic sock, and placed within a prosthetic socketof a prosthesis including a locking stud and a locking stud mechanism,according to the present invention.

FIG. 2 depicts the prosthetic sock of FIG. 1 in more detail.

FIGS. 3a and 3b depict an alternate prosthetic sock according to thepresent invention.

FIG. 4 depicts a partial cut-away view of the prosthetic sock of FIG. 2.

FIG. 5 depicts the apparatus of FIG. 1 used with a residual leg abovethe knee.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1. depicts a prosthesis 10 being worn by a user 12. A residual limb14 is contained within a suction socket sleeve 16. Sleeve 16 maycomprise, for example, silicone, and provides a snug fit about residuallimb 14, the shape of sleeve 16 conforming to the shape thereof. Suctionsocket sleeve 16 is also sometimes referred to as a "roll-on-siliconesocket," a "suspension liner" or a "socket insert, suction suspension."Lower end 18 of sleeve 16 is provided in any appropriate manner with alocking stud 20. Locking stud 20 fits within locking stud mechanism 22and couples thereto such that sleeve 16 stays within prosthetic socket23 of prosthesis 10. Sleeve 16 is covered with a prosthetic sock 32having an opening at end 18 for protrusion of the locking stud.Prosthesis 10 is embodied with the shape, size and appearance of anatural lower leg. Accordingly, as is well understood, surface materials24, such as laminated plastic and foam, are supported on an internalstructural frame 26. The lower portion of this support frame may be madeof, for example, light-weight metal members, simulating a natural ankleand foot. The upper structural part of prosthesis 10 consists of a rigidplastic cup 30 formed to the shape of the residual limb 14. The lowerend of rigid plastic cup 30 is formed about the locking stud mechanism22 and, thus, effectively serves as a housing therefor.

To accommodate periodic fluctuations in the size of the residual limb14, due to expansion and contraction thereof, maintain and adjust thecompression factors needed for a proper fit, prosthetic socks of varyingthicknesses and combinations are used. As used herein, the term "sock"includes what are sometimes referred to as "sheaths", which are verythin socks made of, for example, nylon. These prosthetic socks arepulled over the suction socket sleeve 16. An opening at the distal endof the sock allows the locking stud 20 therethrough to engage thelocking stud mechanism 22. One skilled in the art will understand thevarious ways in which locking stud 20 and locking stud mechanism 22 maybe coupled, as well as the various forms they may take.

The use of suction socket sleeves with a locking stud to suspend aprosthetic limb to the residual limb of the amputee provide an excellentvertical suspension force. However, when this method is used for aprosthesis above the knee (see FIG. 4), it becomes difficult to stop orcontrol horizontal rotational movements of the residual limb within theprosthetic socket. Traditionally, ancillary suspension systems, such asbelts and straps, have been used to control the rotational movement.Although such systems may decrease the rotational movement, theycomplicate the donning process for the amputee, restrict motion andincrease discomfort. Rather than adding additional mechanisms to theprosthesis donning process, the present invention seeks to provide a newprosthetic sock for reducing or preventing the movement of the residuallimb relative to the prosthesis.

FIG. 2 depicts a prosthetic sock 32 according to the present invention.Although described with respect to the residual limb 14 of FIG. 1, itwill be understood that the present invention is useful with any type ofresidual limb on the body, for example, above-the-knee (see FIG. 4) orarms. Prosthetic sock 32 comprises a preferably stretchable material 34,and movement-opposing patch surfaces 36 and 38. Material 34 stretches toconform to the shape of the residual limb, and is preferably made of amaterial providing comfort and cushioning for the user, such as, forexample, cotton. Other possible materials include, for example, wool,acrylic/lycra, polypropolene and rayon. As shown in FIG. 2,movement-opposing patch surfaces 36 comprise a number of spaced verticalstrips of a movement-opposing material, such as latex, integral with thestretchable material 34. It will be understood that the inner surface ofprosthetic sock 32 also has a movement-opposing patch surface disposedopposite each of the patch surfaces on the outer surface (see FIG. 4).As shown in FIG. 2, there are four such patch surfaces 36, including apatch surface on the back side thereof. Movement-opposing patch surface38 is toroidally shaped with an opening 40 for passage of locking stud20. Another such patch surface 38 is oppositely disposed on the innersurface of prosthetic sock 32. Preferably, the use of circumferentialpatch surfaces (i.e., rings) around stretchable material 34 is avoided,since this may affect the stretching ability of sock 32, requiring anarray of different size socks to provide a proper fit.

One way to provide movement-opposing patch surfaces 36 and 38 is tolaminate a movement-opposing material onto the inner and outer surfacesof the sock so that the inner and outer surfaces are saturated with themovement-opposing material. The preferred use of vertical strips allowsnormal expansion of the stretchable material 34 and adaptation to theshape of the residual limb. Another way to provide movement-opposingpatch surfaces 36 and 38 is to remove a portion 42 of material 34 forinsertion of a patch 44, and sew 46 the patch onto the stretchable sockaround the periphery thereof (see FIGS. 3a and 3b). When the secondmethod is employed, a single movement-opposing patch provides themovement-opposing surfaces on both the inner and outer surface of theprosthetic sock.

Although shown in FIG. 2 as vertically disposed strips ofmovement-opposing material, movement-opposing patch surfaces 36 may takea variety of forms, such as a larger number of smaller patch surfaces.In addition, the shape of the patch surfaces may vary. For example, thepatch surfaces may have a round shape or a square shape. It will also beunderstood that a prosthetic sock according to the present invention maynot have distinct movement-opposing patches, but could include a sockwith a movement-opposing surface on the inside and outside.

FIG. 4 depicts a partial cut-away view of the prosthetic sock 32 of FIG.2, including a movement-opposing patch surface 36 on the outside of sock32 and movement-opposing patch surfaces 47 and 48 on the inside thereof.

FIG. 5 depicts the relevant portion of the apparatus of FIG. 1 used witha residual leg 50 above the knee, with the addition of screw 52 forlocking locking stud 20 within locking stud mechanism 22.

The use of prosthetic sock 32 in the prosthesis-donning process will nowbe described. More specifically, a amputee first dons the suction socketsleeve, and then pulls prosthetic sock 32 thereover. If prepared priorto donning, a suction socket sleeve may be rolled on from the end of theresidual limb toward the body. If the suction socket sleeve includes alocking stud, then an opening in the distal end of the prosthetic sockneeds to be aligned therewith. The internal surface of the prostheticsocket 23 is then moistened with water. The moistening allows easydonning of the prosthesis and, as the water evaporates, themovement-opposing patch surfaces provide the friction component tocontrol the rotational movement (and movement in general). To providethe proper thickness, several such prosthetic socks may be combined,donned over each other, to achieve the proper compression factors. Whenseveral such socks are combined, the movement-opposing patch surfacesare aligned to preserve the friction component. Alternatively,prosthetic socks of different thicknesses may be used such that thecombination of several socks is not necessary.

While several aspects of the present invention have been described anddepicted herein, alternative aspects may be effected by those skilled inthe art to accomplish the same objectives. For example, the size, shape,number and/or placement of the movement-opposing patch surfaces mayvary. As another example, the type of movement-opposing material mayvary. As still a further example, the type of material used for thestretchable sock portion of the prosthetic sock may vary. Accordingly,it is intended by the appended claims to cover all such alternativeaspects as fall within the true spirit and scope of the invention.

I claim:
 1. Apparatus for reducing movement of a residual limb relativeto a prosthetic socket of a prosthesis, comprising:a prosthetic sockfabricated of a first material and having an inner surface and an outersurface; and a movement-opposing material disposed only partially onsaid inner surface and disposed only partially on said outer surface,said movement-opposing material comprising a second material, saidsecond material being different from said first material of saidprosthetic sock, said movement-opposing material disposed on said innersurface opposing movement of said residual limb relative to saidprosthetic sock and said movement-opposing material disposed on saidouter surface opposing movement of said prosthetic sock relative to saidprosthetic socket, wherein said movement-opposing material is disposedon said inner surface and said outer surface so as to leave a pluralityof areas about a circumference of said prosthetic sock without saidmovement-opposing material.
 2. The apparatus of claim 1 wherein saidprosthetic sock comprises a stretchable cloth material.
 3. The apparatusof claim 2 wherein said stretchable cloth material comprises cotton. 4.The apparatus of claim 1 wherein said plurality of movement-opposingmaterial comprises latex.
 5. The apparatus of claim 1 wherein saidmovement comprises rotational movement.
 6. A system for reducingmovement of a residual limb relative to a prosthetic socket of aprosthesis, comprising:a suction socket sleeve for placing over saidresidual limb, said suction socket sleeve conforming to the shape ofsaid residual limb; and apparatus for covering said suction socketsleeve prior to placement within said prosthetic socket, comprising:aprosthetic sock for placing over said suction socket sleeve, saidprosthetic sock being fabricated of a first material and having an innersurface and an outer surface, and a movement-opposing material onlypartially disposed over said inner surface and said outer surface, saidmovement-opposing material comprising a second material, said secondmaterial being different from said first material of said prostheticsock, wherein said movement-opposing material disposed on said innersurface opposes movement of said suction socket sleeve relative to saidprosthetic sock and wherein said movement-opposing material disposed onsaid outer surface opposes movement of said prosthetic sock relative tosaid prosthetic socket, wherein said movement-opposing material isdisposed on said inner surface and said outer surface so as to leave aplurality of areas about a circumference of said prosthetic sock withoutsaid movement-opposing material.
 7. The system of claim 6 wherein saidsuction socket sleeve comprises a silicone suction socket sleeve.
 8. Thesystem of claim 6 wherein said prosthetic sock comprises a stretchablecloth material.
 9. The system of claim 8 wherein said stretchable clothmaterial comprises cotton.
 10. The system of claim 6 wherein saidmovement comprises rotational movement.
 11. A method of using aprosthetic sock to reduce movement of a residual limb relative to aprosthetic socket of a prosthesis, said prosthetic sock being fabricatedof a first material and including a movement-opposing material partiallydisposed over an inner surface and partially disposed over an outersurface of said prosthetic sock, said movement-opposing materialcomprising a second material, said second material being different fromsaid first material, wherein said movement-opposing material is disposedon said inner surface and said outer surface so as to leave a pluralityof areas about a circumference of said prosthetic sock without saidmovement-opposing material, said method comprising the steps of:placinga suction socket sleeve over said residual limb, said suction socketsleeve conforming to the shape of said residual limb; placing saidprosthetic sock over said suction socket sleeve, wherein saidmovement-opposing material disposed on said inner surface opposesmovement of said suction socket sleeve relative to said prosthetic sockand wherein said movement-opposing material disposed on said outersurface opposes movement of said prosthetic sock relative to saidprosthetic socket; and inserting said residual limb with said suctionsocket sleeve and said prosthetic sock thereon into said prostheticsocket.